New rule: Define @todo format

Full scope: https://github.com/dgroup/arch4u-pmd/milestone/3?closed=1

See #113, release log:

• 73ca4b5 by @dgroup: #113: Remove 0pdd from project
• d1ff878 by @dgroup: #113: Use single format of TOD...
• c997637 by @dgroup: #113: Todo inspection
• 9243756 by @dgroup: #136: Reconfigure ShortClassNa...
• 1bb7562 by @dgroup: #133: Reconfigure UseUtilityCl...
• a9a06b9 by @dgroup: #133: Reconfigure UseUtilityCl...
• 411c5fd by @dgroup: #131: Bump github/codeql-actio...
• a2923cb by @dgroup: #129: Disable AtLeastOneConstr...
• 4aa8b3d by @dgroup: #129: Disable AtLeastOneConstr...
• 12208d0 by @dependabot[bot]: Bump github/codeql-action from...
• 68a343f by @dgroup: #129: Add support for ignore c...
• df61625 by @dgroup: #113: Todo inspection
• 2ee5581 by @snyk-bot: fix: upgrade org.openjdk.jmh:j...
• c66d813 by @dgroup: #126: Upgrade net.sourceforge....
• 046ea1d by @snyk-bot: fix: upgrade net.sourceforge.p...
• 4418981 by @dgroup: #108: Ensure that readme has n...
• fc2238c by @dgroup: #115: Update issue templates
• c41e029 by @dgroup: #115: Update issue templates
• 0d3d593 by @dgroup: #115: Add default bug template
• b2c9945 by @dgroup: #115: Add default feature requ...
• and 11 more...

Released by Rultor 1.70.6, see build log